Capture and trial

Öcalan went to Russia first and from there moved to various countries, including Italy and Greece. In 1998 the Turkish government requested the extradition of Öcalan from Italy. He was at that time defended by Britta Böhler, a high-profile German attorney who argued that he fought a legitimate struggle against the oppression of ethnic Kurds.He was captured in Kenya on 15 February 1999, while being transferred from the Greek embassy to Jomo Kenyatta International Airport in Nairobi, in an operation by the Millî İstihbarat Teşkilâtı (Turkish National Intelligence Organization) reportedly with the help of the CIA. George Costoulas, the Greek consul who protected him, said that his life was in danger after the operation.Speaking to Can Dündar on NTV Turkey, the Deputy Undersecretary of the Turkish National Intelligence Organization, Cevat Öneş, said that Öcalan impeded American aspirations of establishing a separate Kurdish state. The Americans transferred him to the Turkish authorities, who flew him back to Turkey for trial. His capture led thousands of Kurds to protest at Greek and Israeli embassies around the world. Kurds living in Germany have been threatened with deportation if they continue to hold demonstrations in support of Öcalan. The warning came after three Kurds were killed and 16 injured during the 1999 attack on the Israeli consulate in Berlin.

After his capture, Öcalan was held in solitary confinement as the only prisoner on İmralı island in the Sea of Marmara. Although former prisoners at İmralı were transferred to other prisons, more than 1,000 Turkish military personnel were stationed on the island to guard him. A state security court consisting of three military judges was convened on the island to try him. Öcalan was charged with treason and separatism and sentenced to death on the 29 June 1999.In the same verdict it was declared he was banned from holding public office for life. In January 2000 the Turkish government declared the death sentence was delayed until European Court of Human Rights EU had reviewed the verdict. Upon the abolition of the death penalty in Turkey in August 2002, in October 2002 the security court the sentence was commuted to life imprisonment.The Kurdish Human Rights Project (KHRP) may have aided this case's decision.

Following the commutation, Öcalan remained imprisoned on İmralı, and was the sole inmate there. In November 2009, Turkish authorities announced that Öcalan would be relocated to a new prison on the island and that they were ending his solitary confinement by transferring several other PKK prisoners to İmralı. They said that Öcalan would be allowed to see them for ten hours a week. The new prison was built after the Council of Europe's Committee for the Prevention of Torture visited the island and objected to the conditions in which he was being held.

In 2005, the European Court of Human Rights ruled that Turkey had violated articles 3, 5 and 6 of the European Convention of Human Rights by granting Öcalan no effective remedy to appeal his arrest and sentencing him to death without a fair trial. Öcalan's request for a retrial was refused by the Turkish court.